Among the alicyclic compounds of formula (I), there are a few of prior known structure. These are namely, methyl-, ethyl- and t-butyl cyclopentylidene acetate [R.sup.2 =R.sup.3 =H; R.sup.1 =methyl, ethyl and t-butyl, respectively, in formula (I)], which compounds have been described in J.Chem.Soc., 1934, 610; idem 1932, 2461 and J.Org.Chem., 27,293(1962), respectively. It has to be noted however that the cited literature does not mention nor suggest any possible utility of the given compounds as perfuming ingredients. Hitherto, their olfactive properties have not been recognized and consequently no attention has been devoted by the man in the art to their utilization.